Who Is The Monster on the water ?!!

i am waiting to speak to Ben Ainslie at the Royal Ocean Racing Club, a grand Georgian townhouse next to St James's Park in London. To be honest, I 'm surprised I 've been allowed in I 'm not dressed for a yacht club. It's a relief to see that Britain's most successful sailor is also in jeans. He's being interviewed by television news first. It's not often that TV news bothers much with sailing, but Ainslie's coveted. He's just won the America's Cup, the biggest prize in the sport. 

I 'm surrou. 

August 2005, Cowes. 

A team of young trainee keelboat sailors is captained for one race in the Solent by Ben Ainslie, then 28. He's already a star. The previous year he won a gold medal at the Athens Olympics. Four years before that, in Sydney, he also won gold. And four years before that, in Atlanta, he won silver, when he was only 19. He will go on to win golds at the 2008 and 2012 Games, too, making him the most successful Olympic sailor ever. 

This race in the Solent has nothing to do with th. 

There are better, and better-documented, examples of Ainslie's ferocious competitiveness, which now and then can appear to border on psychopathic. The way he hunted down a Brazilian sailor, unsportingly some said, to ensure gold in Sydney ; a human-torpedo assault on a press boat he took offence to ; the rage at the Olympics last year ("They 've made me angry and you do n't want to make me angry"), which naturally spurred on the charge to yet another gold. 

What strikes me most, though, seeing it in the. 

September, 2013, San Francisco Bay. 

(This part you probably know by now.) The final of the 34th America's Cup, the competition that started 162 years ago in Cowes and is now the oldest trophy in world sport, looks like it's all over. The holders, software billionaire Larry Ellison's Team Oracle USA, are being outperformed and outsmarted by the challenger, Emirates Team NZ. In a desperate, last ditch attempt to salvage the situation, Ellison does something bold. He sacks his tactician and puts a. 

October 2013, Royal Ocean Racing Club. 

We 've caught up with ourselves too, the TV news is done, and now we 've got the Fastnet Room to ourselves. Well, apart from his manager, and a lawyer. Anyway, nice one, the America's Cup! How did he do that then? "Well, it's not a case of how did I do it" Oh, here we go he's going to be all modest, and it's going to be all about the team effort, zzz. "No, it's true. It is a team effort. There were 120 guys on the team and 11 of us on the water. It's. 

http://www.theguardian.com/sport/video/2013/sep/26/ben-ainslie-americas-cup-oracle-victory

I think the problem is that I 've got demesne Ben Ainslie here polite, charming and saying all the right things. But it's not the same shy, invisible land Ben Ainslie I met eight years ago (he claims to remember that meeting, by the bye ; I do n't believe him). I guess another couple of Olympics, a knighthood and now the America's Cup is n't going to knock anyone's dedication overmuch. He's certainly more relaxed than earlier, better company, chattier. 

I ask him about the Jekyll and Hyde thing, tu. 

He's spoken before about being bullied at school. "I think it probably toughened me up a little, made me want to prove myself, because when you 're at school and you 're not really great at anything and struggling a little, then, you know". 

Is there's anyone particularly from back then he'd like to stick it to? You know, look at you, Colin Tucker (or whoever), stacking shelves at Asda I just won the America's Cup, and I 'm a Sir. But he's not having any of it. "It was n't anything outrageous, i. 

Now is the time to act, though, with sailors and designers available after the end of the last one, and the buzz still on the breeze. It worked this time, he says, probably for the first time, as a sporting event and a television spectacle. Close racing, extraordinary high-performance catamarans almost literally flying around at over 50mph, proper athletes working their arses off, a spectacular setting, TV footage (which TV companies are prepared to pay for) and graphics that meant it was actually possible to know what the hell was going on, not to mention that comeback – it all came together into something properly exciting.

A comparison with Formula One isn't unreasonable, he claims, "with the speed of these boats, the performance thing, and the physicality". Like F1, the America's Cup needs to bring costs down. "If that's done properly then hopefully you will retain that level of excitement, getting a few more boats, and have a great circuit on your hands.

Isn't sailing just a sport for toffs, though? I'm looking round, at the Georgian panelling and the yachty portraits. "That's about the history of sailing," says Ainslie, who says he isn't a toff ("Do I look like a toff?"). "We've got a really proud maritime history, and it's beautiful. You wouldn't want to change that. But it's not America's Cup racing. That's the future. I see them as very separate. In the past it's been a sort of billionaires' plaything. Any sport at the highest level is expensive. Winning the Tour de France isn't cheap, and that's a cycling race. It's a misconception that sailing's about gin and tonics on the aft deck. This event, and the Olympics for the past 15 to 20 years, have shown that a lot of grit and determination and hard work go into it. It's not a toff's sport, it's a proper sport."

He gets quite passionate defending his sport, particularly about accusations of over-toffiness, it seems. Not too passionate I hope – we know what happens when he gets angry, and I wouldn't want to be on the receiving end of that, even on land. Your right of way, Ben – Sir Ben – even if it isn't.

Preparing The Boat 2

1. 2
   Adjust for the wind. Sailboats cannot sail directly into the wind. As shown below, the red zone in the diagram indicates a "no go" zone when under sail. To sail to windward, a sailing vessel must sail about 45-50 degrees off the wind and change direction by tacking (or zig-zag).
   
   • Turn the boat to the left (port) or right (starboard) so it's about 90 degrees off the wind. This is known as a beam reach.
   • Pull on the main sheet (trimming) until the sail is around 45 degrees away from straight back (aft). This is a safe place for the main while you trim the jib.
   • You will start moving and tilting (heeling) away from the wind. A heel of more than 20 degrees usually indicates that you're being overpowered. Releasing the mainsheet momentarily (breaking the main) will lessen the amount of heel, and you will return to a more comfortable sailing angle of 10 to 15 degrees of heel.
2. 3
   Trim the jib sheets. Although the mainsail is hoisted first, it is the jib that is trimmed first. There are two jib sheets, one for each side of the boat. Pull on the jib sheet on the the side away from where the wind is coming from (leeward side). This is the active sheet while the other is called the lazy sheet.
   • The jib will form a pocket; trim the sail until the front edge just stops luffing. Keep your hand on the tiller (or helm) and stay on course!
3. 4
   Trim the mainsail. Let out the main sheet until the front edge just starts to luff, then pull it back just until it stops.
   • If you or the wind hasn't changed direction, this is the most efficient place to set the sails. If anything changes, you have to adjust them in response.
   • You have just entered the world of the sailor, and you will have to learn to do many things at once, or suffer the consequences.
4. 5
   Watch the front of the sail edge on the main and jib. If it starts to luff, you have two choices: tighten the sail sheet until it stops luffing, or steer away from the wind (bear off). When the sail luffs, it means that you are heading too much into the wind for your current sail setting. If you bear off slightly, (away from the wind) your sails will stop luffing.
5. 6
   Watch your wind indicators (telltales). If you see it change so that the wind is coming from a direction that is more behind you, you will be wasting energy. Let out the sail till it luffs, and tighten again till it stops. You will be doing this constantly; watching the sails, the telltales, and trimming sails if for no other reason than to see where you're at.
   • When the wind is at your back and side (aft quarter), it's called a broad reach. This is the most efficient point of sail as both sails are full of wind and pushing the boat at full force.
   • When the wind is at your back, you are running with the wind. This is not as efficient as reaching, because the jib is covered by the mainsail and not filling with air.
   • When running with the wind, you can sometimes you can pull the jib over to the other side of the boat where it will fill. This is called wing-on-wing, and you have to maintain a steady hand on the tiller to keep this sail configuration. Be sure to be vigilant of obstacles and other vessels, as having both sails in front of you blocks a significant portion of your view.
   • Be careful—when the boat is running, the sails will be way off to the side, and because the wind is basically behind you the boom can change sides suddenly (jibeor gybe), coming across the cockpit with quite a bit of force.
   • If you have a wind direction indicator at the top of your mast, do not align the boat so that the wind indicator points at the mainsail. If it does, you are sailing with the boom on the windward side (sailing by the lee) and are at high risk of an accidental jibe. When this happens the boom can hit you with enough force to knock you unconscious and out of the boat (overboard).
   • It's a good practice for beginners to pull the sail in a bit when running so it doesn't have far to go if it jibes.
6. 7
   Close reach. Turn the boat slightly into the wind, maybe 60-75 degrees off the wind. You will have to pull the sheets tighter so the sails are more closely in line with the boat. This is called a close reach. Your sails are acting like the airfoil of an airplane: the wind is pulling the boat instead of pushing it.
7. 8
   Close haul. Continue to turn into the wind (head up) and tighten the sheets until you can go no farther (the jib should never touch the spreaders on the mast). This is called close-hauled, and is as close as you can sail into the wind (about 45-60 degrees off the wind). On a gusty day, you will have all kinds of fun with this point of sail!
8. 9
   Sail into the wind to a destination. Sail a heading that is as close to the wind as you can, close-hauled. On most sailboats this will be about 45 degrees to the wind.
   • When you've gone as far as you think prudent, suddenly turn the boat through the wind (or changing direction by tacking), pulling the jib sheet out of its cleat or straight up off the winch drum as the front of the boat (bow) turns through the wind.
   • The main and boom will come across the boat. The mainsail will self-set on the other side, but you will have to quickly pull in the jib sheet on the opposite side on its cleat or winch, while steering the boat just to the point where the mainsail begins to draw again.
   • If you do this correctly, the boat won't slow down much and you will be sailing to windward in the other direction. If you're too slow tightening the jibsheet again and the boat bears off the wind too much, don't panic. The boat will be pushed sideways a little until it gains speed.
   • Another scenario would be to fail to put the bow of your boat through the wind quickly enough and the boat comes to a complete stop. This is known as being in irons, which is embarrassing, but every sailor has experienced it. Being in irons is easily remedied: when the boat begins moving backwards you will regain steerage.
   • Point the tiller in the direction you wish to go and tighten the jib sheet to windward, (backwinding the sail). The wind will push the bow through the wind. Once you've completed your tack, release the sheet from the winch on the windward side and pull in the sheet to leeward and you'll be on your way again.
   • Because speed is so easily lost when tacking, you'll want to perform this maneuver as smoothly and quickly as possible. Keep tacking into the wind until you get to your destination.
9. 10
   Go easy when learning. Understand that it's best to practice on calm days, and so, for example, learn to reef your boat (make the sails smaller). You will need to do this when the wind is too strong and you're being overpowered.
   • Reefing almost always needs to be done before you think you need to!
   • It's also a good idea to practice capsize procedures on a calm day too. Knowing how to right your boat is a necessary skill.
10. 11
    Sail safely. Remember that your anchor and its cable (rode) are important pieces of safety gear and can be used to stop your boat from going aground or can even be used to get the vessel floating again should a grounding occur.
    
    
    

Hoisting The Sails

Attach the sails. Secure the bottom front (tack) of the mainsail and jib to their respective shackles on the boom and the bow of the boat.

• There will be a small line (outhaul) attaching the back of the mainsail (clew) to the boom and its cleat. Pull it hand-tight in the cleat. This tightens the foot of the sail.
• Hoist the mainsail by pulling down on its halyard all the way until it stops. It will be flapping around (luffing) like crazy, but thats ok for a short period of time. (Excessive luffing will drastically reduce the life and durability of the sail).
• The leading edge of the sail (luff) must be tight enough to remove folds, but not so tight as to create vertical creases in the sail.
• There will be a cleat in the vicinity of the halyard where it comes down from the top of the mast. Cleat the halyard. Using the jib halyard, raise the front sail (jib, genoa or simply the headsail), and cleat the halyard off. Both sails will be luffing freely now. Sails are always raised mainsail first, then the jib, because it's easier to point the boat into the wind using the main.

Preparing The Boat

1 - Perform a detailed visual check. Inspect all the standing rigging—the cables and ropes that support the mast—including the turnbuckles and cotter pins securing the rigging to the hull. Many sailboats have dismasted because a 15-cent cotter pin was missing!

• Check the lines (running rigging) that raise and control the sails (halyards and sheetsrespectively). Make sure that they are separated, not wrapped around each other or fouled on anything else, and that they all have a figure-eight knot or other stopper knot on the free (bitter) end so they cannot pull through the mast or sheaves.
• Pull all lines out of their cleats and off their winches. There should be nothing binding any line; all should be free to move and be clear at this point.
• If you have a topping lift—a small line that holds the back of the boom up and out of the way when the sail isn't in use—let it out until the boom sags downward freely, then re-tie or re-cleat it. Watch out for the boom; it's just swinging around at this point; being made of aluminum, it will cause a painful "clunk" if it happens to hit you or your crew. The boom will return to its normal position when you hoist the mainsail.
• Attach thetiller. Be sure that it is properly attached to the back of the boat (transom). Your sailboat is now prepared for you to hoist the sails!                                                       
• 
  
• 2 - Determine the wind direction. If your boat doesn't have some kind of wind direction indicator (windex) at the top of the mast, tie a couple nine-inch pieces of old cassette tape, VHS tape, or oiled yarn to the shrouds—the rigging cables that hold up the mast.
• Place them on each side, about four feet up from the sides of the boat.
• To sail effectively, you will need to know the apparent direction of the wind .
• Some sailors find cassette tape to be just too sensitive for this purpose. If that's the case with you, try using VHS tape instead.

• 3 - Point the boat into the wind. The idea is to have the minimum amount of wind resistance when raise the sail, with the sail straight back. In this position, the sail won't be snagging on any shrouds or any other hardware, either. This isn't always easy. The boat won't turn readily because it's not moving (under way). Do the best you can, but be prepared to work for it!

• Here's a handy tip: if the water is not deep at your dock, or if you have no side pier, walk the boat out away from the dock and anchor it into the sand, and the boat will automatically point itself into the direction of the wind!

• 
  
  

How to Sail a Boat ?!!

You've always wanted to learn to sail, but the different parts of the boat, the unfamiliar jargon, and maybe even the mystique of sailing have left you looking for a flotation device just to keep your head above it all! This article is for you: it will cover the hardware present on most small sailboats, as well as common sailing techniques, terms and definitions, the names of the different pieces of hardware, and much more. This will get you started, but be sure you spend time with an experienced sailor and your boat before you venture out on the water on your own.

470 Aerodynamics

470 Aerodynamics

We have seen in events like the America«s Cup or the Admiral«s Cup that sailmakers are taking a more and more scientific approach in their sail development-programs. WB-Sails has studied 470-sails with the help of the most modern computer tools. This article first appeared in "470 Times" in June -92. WB-Sails chose the 470-rig as one of the first testing grounds for their aerodynamic analysis-program MacSail for several reasons: Firstly, with our long experience of the 470-class we were confident that the shapes of these sails represented well today«s state-of-the art. Also, we had accurate shapes available through normal photography as well as photogrammetry. Another important factor was that the level of racing in the 470-class represents (both internationally & nationally) the highest standards. The MacSail-calculation program is based on a system called "vortex-lattice method". In this method, the sails are replaced by a 3D-grid, dividing both mainsail & jib into approximately 100 elements. Flow velocity is calculated in the center of each element, on both leeward and windward sides of the sails, taking also into account the effect of the jib wake (backwind) on the mainsail. From flow velocity, the pressure can be deduced, and by adding the windward side pressure to the leeward side suction, the pressure difference in each element can be obtained. This pressure acts perpendicular to the element surface, forming a small force vector. Summing up all these small vectors in each element gives the magnitude and direction of the total force acting on the jib & the mainsail. An example of the results can be seen in the illustrations below. These examples are calculated in a wind of approximately 6 m/s (13 knots): Jib Main Both Driving force in kp 10,5 11,5 22,0 Heeling force in kp 28,5 55,5 84,0 Heeling moment in kpm 58,5 174,0 231,5 As you can see, the jib seems to contribute much more (relatively) to boatspeed than the mainsail, but don«t get it wrong: it only does this because it is working in conjunction with the main. In fact, the jib is receiving a strong "lift" from the main, while the mainsail is experiencing a bad header due to the jib (the jib, after all, is in a "safe leeward position"). Take the main out, and the jib will lose its magic. Note how very small the actual driving force pulling the boat forward is, some 22 kilos. In this light, it is easy to understand, how important every little detail, from aerodynamic clothing to an open bailer or dragging spinnaker sheet, not to mention hitting a wave badly, is to getting the maximum out of your boat. 470 Main & JibPressure difference at apparent wind speed 8 m/s apparent wind angle 23 degrees For the purpose of the calculation, the sails are divided into approximately 100 elements each. Different shades/colours represent a different surface pressure according to the table on the left. You can tell from the colours that the pressure is far greater in the upper part of the sails, and even more so in the jib than the mainsail. This is partly due to the triangular shape of the sails, and partly to the intensional shaping of the sails to minimize vortex induced drag.The jib represents 40% of the total force of the sails, although it is only 30% of the area. Nearly 50% of the forward drive comes from the tiny jib. Flow velocity on the leeward sideThe difference in flow velocity on the windward & the leeward sides creates the pressure difference. The pressure difference is the cause of the driving & heeling forces excerted by the rig onto the hull. Here we can see the calculated flow velocity on the leeward surface of the sails , in a free stream velocity (apparent wind speed) of 8 m/s. A flowchart such as this gives the saildesigner a wealth of useful information. You can see, how the flow is accelerated on the surface of both sails so that the speed of the flow is nearly everywhere greater than the wind speed. Near the head of the sails the speed is almost doubled, ie. 14-15 m/s. The influence of the jib can clearly be seen on the main surface - the flow is decelerated in the slot between the two sails, not accelerated, as you often hear claimed. The velocity on the surface of the jib is larger than on the main, and even in most of the leech area it is higher than the wind speed. As a result, the flow is less prone to "separate", and thus the jib can produce a greater drive in conjunction with than mainsail than it would alone. The flow separates, if it is forced to slow down too much too fast. The jib maintains higher velocities all the way down, because the foot lies on the deck, while in case of the mainsail, the pressure difference tends to even out under the boom, thus making the lower part of the sail less efficient. The flow has to slow down to the free stream speed in the leech of the mainsail, which makes it prone to separation. Separation always occurs first in the head of the sails, where acceleration & the following deceleration is big. In the front part of the main, flow velocity is nearly the same as wind speed - there«s hardly any pressure difference, the sail is close to backwinding. Although calculations such as these give a wealth of useful information to the saildesigner, it would be wrong to expect a miracle shape to come out of the computer as a result. We can only optimize the sails for one given wind condition at the time - and although we can simulate mast bend and forestay sag in the computer, the true art and skill of the sailmaker comes out in the intricate balance between the seam-induced, moulded shape and the luff curve shape, combined with the rig characteristics and the fabric strech, to produce a suit of sails versatile enough to power the boat from the lightest zephyrs to the choppy seas in heavy breezes. So, even in this computer-age, the ultimate proving ground of a new suit of sails remains the race course, the way it should be.

Draft position

Draft position

I was interested to read what Frank Bethwaite had to say on the position of maximum draft in his "Tasar" dinghy class -- he was comparing maximum draft at 25% against 50% of chord:

"My authority for [my] statements are experiment and observation but primarily model aircraft glide tests with different wing sections. The dynamics of sailing to windward at max VMG in lighter wind are the same as the dynamics of a glider which is looking for minimum sinking speed. A test model with a wing with a thin section and max camber at 25% from the leading edge was efficient at one particular speed. With a wing of identical shape and weight but with max camber at 50% (ie. a circular arc section) it was as efficient as the “knuckled” section [ie max draft at 25% of chord] at its best point, but it maintained this efficiency over a wide speed range. In smooth air the two sections could glide and lose height as well as each other. In rough air the knuckled section became unstable and the model sank faster, while the circular arc section continued to fly steadily in the rough air, the model remained stable and sank more slowly."

This was interesting on two counts.  One was that Graham Bantock uses an aerofoil section on his rudder which he tells me is pretty much the same as that used on competition (full size) gliders.  Both model yacht and full-size glider operate at similar Reynolds numbers.

The other was that Frank Bethwaite was clearly saying that draft forward was not advised.

This is only half of the story, however.  One of the key things about draft amount and position is that they affect the entry angle -- and it is the entry angle which is so important while beating.

Entry angle depends upon draft amount and position

Will Gorgen sent me some comments on entry angle and its importance:

However there is another principle that you need to keep track of. That is the incidence angle at the leading edge.  As you pull the draft forward, you change the angle of the leading edge relative to the incoming air flow. This causes your angle of incidence between the leading edge and the incoming flow to decrease.  In the extreme, this will cause the front of the sail to luff and will effectively force you to sail lower (foot) in order to keep your sail from luffing. When you sail lower, you increase the overall angle of attack of the sail and move yourself closer to stall.

Thus, moving your draft too far forward can cause your sail to stall, and moving your draft too far back can cause your sail to stall. There is an optimal draft position in between these two competing forces that will determine your optimal draft position.  This is often determined by your individual sailing style. For people who like to point high, you generally need the draft of the sail further back in order to keep the entry of the sail at a positive angle of incidence and prevent the sail from luffing.  For people who like to foot, you can tolerate the draft further forward and sail with a higher overall angle of attack and thus carry more force in the sail.  Of course optimal VMG depends on carefully balancing the lack of windward progress with the extra speed that you get when you foot.

Moving your draft further forward allows you to generate more drive in the sails and tolerate a higher angle of attack, but at the expense of pointing.